<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<link rel="stylesheet" type="text/css" href="css/例5.9.css"/>
		
		<h1>一级标签</h1>
		
		<h2>二级标签</h2>
		
		<h3>三级标签</h3>
		
	</body>
</html>
